The thesis focuses on Oil tank foundation system. The finite element code PLAXIS and PLAXIS 3D Foundation were used for the numerical simulation. The research work is aimed at pursuing the objectives: (1) Numerical analysis for single pile, pile raft analysis and compare to some other established methods to validate the FEM program (2) Back analysis of the centrifuge data of 37 end-bearing pile group underneath the sand pad supporting a model oil tank.
The research work done can be summarized as: (1) Single pile was modeled in both 2D Axisymmetry using Plaxis v8 and 3D using Plaxis 3D Foundation. The results from both analyses are compared in order to check the accuracy of Plaxis 3D Foundation program. Plaxis 3D Foundation also is validated in prediction behavior of a piled raft with 6 other established methods (2) numerical analyses to study the effect of pile cap area, thickness of overlying granular material, number of piles, and stiffness of bed layer of a pile foundation system supporting an oil tank over soft clay. The load distribution among piles, the load transfer characteristics, the maximum settlement, the differential settlement, the shape of settlement and the arching in soil are investigated in each case study. The results are compared to centrifuge data.